The hermetic rotary compressor, in general, discharges compressed refrigerant gas into a hermetic case, so that the inside of the hermetic case becomes high pressure atmosphere. A piston formed of off-center rollers is accommodated in a cylinder room of the compressor. A front end of the vane is urged by a spring against the surface of the piston. The cylinder room is partitioned by the vane into a sucking space and a discharging space. The sucking space is connected to a sucking tube, and the discharging space opens into the hermetic case.
Unexamined Japanese Patent Publication No. H01-247786 discloses a hermetic rotary compressor having two cylinders. This compressor can change its air-conditioning capacity or refrigerating capacity by using both of the cylinders simultaneously or using one of the cylinders while halting the other one's compressing operation. The compressing operation can be halted by isolating the vane from the piston.
Although the compressor of this type is functionally advantageous over other types, a hermetic vane room is needed and thus placed behind the vane because the vane in a second cylinder room needs to be isolated forcibly from the piston. A vane room, in general, communicates with the inside of the compressor, so that it is always in the atmosphere of lubricant, and actually a sufficient amount of lubricant is supplied to its sliding section. However, the vane room of the compressor disclosed in the foregoing patent does not communicate with the inside of the compressor, so that the vane room forms a hermetic room. The sliding section of this vane thus has a possible problem that it cannot receive a sufficient amount of lubricant, and this problem invites wearing or seizing at the sliding section.